Particle separation and filtration have been used in numerous applications across industries and fields. Examples of such applications include chemical process and fermentation filtration, water purification/wastewater treatment, sorting and filtering components of blood, concentrating colloid solutions, and purifying and concentrating environmental samples. Various macro-scale techniques have been developed for use in these applications including methods such as centrifugation and filter-based techniques. Typically, such techniques require systems that are large, bulky, and expensive and have complex moving components.
In certain cases, micro-scale techniques offer advantages over macro-scale techniques, in that scaling down allows the use of unique hydrodynamic effects for particle sorting and filtration, and thus eliminates the need for large systems with complex moving components. Moreover, micro-scale techniques offer the possibility of portable devices capable of performing sorting and filtration at much lower cost than larger macro-scale systems. However, typical micro-scale sorting and filtration devices can be limited in the amount of fluid they can handle over a specified period of time (i.e., low throughput), potentially placing such devices at a disadvantage to their macro-scale counterparts.